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The synergistic active-passive utilization of solar energy in buildings plays an important role in achieving nearly zero-energy buildings. Building-integrated photovoltaic (BIPV) is a crucial initiative to reduce heating energy consumption, especially in cold climate zones with abundant solar radiation. However, few studies have examined the impact of design parameters of photovoltaic combined vacuum glazing (PVCVG) on building energy efficiency in Lhasa. This study assessed the energy performance of several typical windows and PVCVG with various Window-to-Wall Ratio (WWR) design conditions and investigated how the WWR and orientation of PVCVG influence energy consumption using DesignBuilder7.0 software. The findings indicate that PVCVG exhibits great energy-saving potential in Lhasa, with both orientation and WWR of PVCVG substantially affecting energy consumption. Specifically, when the south-facing WWR exceeds 40%, the energy generated by the three kinds of PV windows can meet the building's requirements. The optimal orientation for PVCVG is southward, followed by east and west orientations. PVCVG reaches optimal energy satisfaction when the south WWR is 85%. This study is expected to provide useful information for improving energy use efficiency in cold climate zones with abundant solar radiation and promoting sustainable building development. [ABSTRACT FROM AUTHOR]

Silicon (Si) is regarded as a promising anode material owing to its high specific capacity and low lithiation potential. The large volume change and the pulverization of silicon during the lithiation/delithiation process hinder its direct energy storage application. This review focuses on the electrospun silicon/carbon (Si/C) nanofiber anode materials for lithium-ion batteries for long-term stable energy storage. Silicon is completely embedded in electrospinning-based carbon nanofibers to form electrospun Si/C nanofibers. It not only creates pore space to buffer silicon volume expansion, but also prevents direct contact between silicon and the electrolyte, consequently forming a stable solid electrolyte interface film. The electrospun Si/C nanofibers solve the pulverization issue of silicon to achieve improved cycling stability. Furthermore, the electrospun carbon nanofibers form a flexible conductive network for surrounding silicon by facilely introducing sacrificial polymers or template agents. The electrospun Si/C nanofibers ultimately promote the lithium-ion transport to achieve rate stability. The silicon source selection and microstructure regulation of the electrospun Si/C nanofibers are overviewed. The silicon sources include the direct utilization of silicon or silicon oxide particles as well as the indirect conversion of silicon-based precursors. The cycling stability regulation of various metal- and metal oxide-modified silicon composites and heterogeneous carbon material-decorated electrospun Si/C nanofibers is summarized. In addition, the microstructure designs of the electrospun Si/C nanofibers associated with the improvement of long-term capacity retention are overviewed. The main challenges in the electrospun Si/C nanofiber anode materials are summarized, and the future perspectives are also proposed. [ABSTRACT FROM AUTHOR]

The sulfuric acid-doping polyaniline (H-PANI-HSO4) are applied to conduct the electrochemical measurement and simulation calculation to investigate the capacitance, electronic structure and energy band properties. The H-PANI-HSO4 growing on graphite carbon paper (H-PANI-HSO4/GCP) is applied as an electroactive electrode to investigate electrochemical properties. The Faradaic capacitance of H-PANI-HSO4/GCP electrode is ascribed to the reversible redox reaction of bisulfate anion doping/dedoping protonated PANI (H-PANI). Cyclic voltammetry measurement at a scan rate of 5 mV s − 1 determines an equivalent mean response current of 0.64 A g − 1 and a capacitance of 128.35 F g − 1 . Galvanostatic charge–discharge measurement determines specific capacitance from 129.06 to 116.88 F g − 1 at current densities from 0.5 to 2.5 A g − 1 . Cyclic voltammetry-based capacitance at equivalent current density of 0.64 A g − 1 is in accordance with galvanostatic charge–discharge-based capacitance at the current density of 0.57 A g − 1 . Electrochemical impedance spectrum measurements indicate that H-PANI-HSO4/GCP exhibits lower charge-transfer resistance, much lower Warburg resistance, higher quasicapacitance than H-PANI-HSO4 to approaching ideal capacitor. Density functional theory calculations indicate that H-PANI-HSO4 has a higher density of states (10.6 electron/eV) and lower bandgap energy (0.481 eV) than H-PANI (5.24 electron/eV, 1.449 eV), indicating its enhanced electronic conductivity. The electronic bandgap energy is accordingly decreased from 0.263 eV for H-PANI-HSO4/GCP to 0 for H-PANI-HSO4/GCP. Electrochemical measurement and simulation calculation investigation proves that H-PANI-HSO4/GCP electrode with anion-doped and protonated state exhibits higher electronic conductivity and capacitance performance to act as superior electroactive material. The LiClO4-interacted oxygen-containing carbon paper is designed to act as electroactive supercapacitor electrode substrates for energy storage application, which involves the polarized electrostatic force-induced interfacial adsorption between LiClO4 and hydroxyl and epoxy groups of OCP substrate. [ABSTRACT FROM AUTHOR]